Method of making a window covering from fabric segments

ABSTRACT

In a method for making a window covering the user selects a first segment of cellular material in which there is a top cell having a top surface, at least one glue line on the top surface and a strip of fabric on the at least one glue line. The strip of fabric and at least a portion of the glue line are removed from the top surface of the top cell and a second glue line is applied to that top surface. A second segment of cellular material is place over the second glue line on the top surface of the top cell of the first segment. The glue line cures and bonds the second segment of cellular material to the first segment of cellular material. If the cellular material has tabbed cells the processes can be used to join the tabs of the two segments together.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 60/561,635, filed Apr. 13, 2004.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention relates to window coverings having a stack of cellularmaterial attached between a headrail and a bottom rail in which thematerial is formed from physically similar remnant pieces of cellularfabric.

2. State of the Art

One common type of window covering has a panel of cellular materialconnected between a headrail and a bottom rail. These window coveringsare sold in standard stock sizes and are custom made by fabricators. Thefabricators buy standard headrails, bottom rails and related hardware aswell as stacks or blankets of cellular fabrics. The fabricators measurethe windows to be covered. Then they select or cut down a standardheadrail and bottom rail for each window and cut a panel of materialfrom the blanket which is the correct width and length for the window.Quite often the fabricator will have segments of these blankets whichare too small to use. Some of these segments may be as much as twelvefeet wide and only three feet long. Typically, this left-over fabric isdiscarded.

In U.S. Pat. No. 6,019,864 Jones discloses a method and apparatus forcombining segments of cellular material to form a composite windowcovering. If necessary, the short segments to be interconnected aretrimmed to a uniform width consistent with the width of a window area tobe covered. Thereafter, a cell of each short length to be connected istrimmed to provide a neat attachment surface strip. Glue beads are runalong each edge of each attachment surface strip of the short length ofcellular fabric to be attached, and the glue covered attachment surfaceis pressed against a clean (non-glued) attachment surface strip of ashort receiving length to which attachment is to be made. Pressure isreleased after initial bonding has occurred. The resulting bond betweenthe two segments is thus comprised of two original glue lines, twostrips of fabric and the new glue beads. This bond will be twice orthree times the thickness of the bonds between all other cells in thecombined stack and is quite noticeable. Consequently, there is a needfor a method of combining segments of cellular and pleated materials ina manner so that the resulting structure has a uniform appearance.

SUMMARY OF THE INVENTION

We provide a method for making a window covering from segments ofcellular or tabbed material. When using cellular material containing aplurality of cells we select a first segment of cellular material inwhich there is a top cell having a top surface, at least one glue lineon the top surface and a strip of fabric on the at least one glue line.Then we remove the strip of fabric and at least a portion of the gluefrom the top surface of the top cell. Next we apply a second glue lineto the top surface of the top cell. Then we place a second segment ofcellular material over the second glue line on the top surface of thetop cell and allow the second glue line to cure thereby bonding thesecond segment of cellular material to the first segment of cellularmaterial.

The strip of fabric and portion of glue could be removed by grinding,milling, cutting or sanding. One might heat the glue to soften it andthen peel or scrape the fabric strip and glue away. One could freeze theglue and then crack the frozen glue to remove the strip of fabric and atleas some of the glue.

The methods just described for joining segments of cellular materialscan also be used for joining segments of tabbed material in which eachtab is comprised of two layers of fabric connected together by at leastone glue line. We first remove the top layer of fabric and at least aportion of the glue line from the bottom layer of the top tab of asegment of tabbed material. Next we apply at least one new glue line tothat bottom layer of fabric. Then we select a second segment of tabbedmaterial in which the bottom tab is a single layer of material. Thissingle layer could have been created from tab comprised of two layers offabric glued together by removing the outermost layer of fabric and aportion of the glue or may have been made to have only a single fabriclayer. Next we place that tab onto the new glue line on the firstsegment of tabbed material and allow the glue to cure thereby bondingthe second segment of tabbed material to the first segment of tabbedmaterial.

The segments of cellular material as well as the segments of tabbedmaterial may have been cut from a wider segment of material.

Other objects and advantages of our method of making a window coveringfrom fabric segments will become apparent from certain present preferredembodiments thereof illustrated in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a fragment of a cellular fabric panel;

FIG. 2 is an end view of the fragment of cellular material shown in FIG.1 in which the fabric and glue are being removed by grinding;

FIG. 3 is an end view of a portion of a cellular material made from alaminated fabric;

FIG. 4 is an enlarged perspective view of a portion of the laminatedfabric used in the cellular material of FIG. 3;

FIG. 5 is an end view similar to FIG. 3 after much of the fabric hasbeen removed;

FIG. 6 is a perspective view of a fragment of cellular material intowhich heated paddles are being inserted to melt the original glue;

FIG. 7 is an end view of a fragment of cellular material after much ofthe original glue has been removed and a new glue line has been applied;

FIG. 8 is an enlarged view of the glue and portion of the fabric shownin FIG. 7;

FIG. 9 is a perspective view of two cellular segments prepared andaligned for bonding;

FIG. 10 is an end view of a fragment of tabbed material; and

FIG. 11 is an end view of two fragments of tabbed material after much ofthe original glue and to layer of fabric has been removed from the tabsto be joined and a new glue line has been applied to one such tab.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A typical single cell material 1 shown in FIG. 1 has a series of cells2, 3 in which adjacent cells are glued together. There may be a singleglue line or multiple glue lines. One common practice is to provide twoparallel glue lines 4, 5 spaced apart a sufficient distance so thatholes for lift cords can be easily drilled through the cellular fabricbetween the glue lines. A fabricator typically purchases cellularmaterial in standard sizes which may be widths of eight to fourteen feetor more and lengths of twelve to fifty feet. From these blankets ofcellular material the fabricator cuts a sufficient amount of material tocover a window. Typically, these pieces will be three to four feet wideand six to eight feet in length. Consequently, it is quite common for afabricator to have left over segments of cellular material. For example,if a fabricator makes three shades which are four feet wide and eightfeet long from a 12′×12′ blanket, he will have a segment of cellularmaterial which is twelve feet wide and four feet long. A window of thissize is quite rare. However, if the fabricator could cut the twelve footsegment into three four feet widths and then bond them together, hewould have a segment that could be used in a four foot wide windowhaving a length up to twelve feet. Since all segments would be cut fromthe same material the segments would match when bonded together.

We provide a method of bonding such segments together in which fabricand a portion of the glue along the top surface of the top cell of thesegment from which other pieces have been cut is removed. It is notpractical to remove all of the glue because some of the original gluewill have migrated between the fibers of the fabric. Nevertheless, asubstantial portion of that glue is removed.

Those skilled in the art will recognize that cellular materials used inwindow coverings have been made from films, paper, woven materials,non-woven materials and composites of one or more films, papers, wovenmaterials and non-woven materials. For ease of reading, the word fabricwill be used to describe and claim the segments used in the presentmethod. However, it should be understood that the word fabric as usedherein includes films, paper, woven materials, non-woven materials andcomposites thereof.

In one preferred method illustrated in FIG. 2 a grinding wheel 8 is usedto grind away any fabric 7 and much of the glue of glue lines 4 and 5.After this fabric and glue has been removed the segment is ready forbeing bonded to another similarly prepared cellular segment. Although weillustrate a grinding head in FIG. 2, any material removal process suchas milling, sanding or cutting could be used.

Some fabrics 10 shown in FIG. 4 are laminates of multiple thin layers offabric. These layers 10 a , 10 b , 10 c and 10 d in the fabric of FIG. 4are point bonded at spaced apart locations 9. When such material 10 isused in a cellular product, shown in FIG. 3, it may be sufficient tosimply remove all but one layer of the multi-layer fabric. This can bedone by grinding as illustrated in FIG. 2 or cutting or even tearing theother layers 10 a, 10 b, 10 cfrom the cellular segment. The resultingstructure would appear as in FIG. 5 in which there is single layer 10 don cell 2. A cellular segment prepared as shown in FIG. 5 is now readyfor bonding to another segment.

Another way of preparing the segments for bonding together isillustrated in FIG. 6. We provide two elongated paddles 11, 12 sized tofit within a cell 2 of cellular material 1. Each paddle has a heatedsurface 13, 14 which presses against the area of the cell having gluelines 4, 5. An insulator 15, 16 is provided on and possibly around theedges of each of the heated surfaces 13, 14. The elongated paddles 11and 12 are placed on either side of the bond area and heatedsufficiently to melt the adhesive 4 and 5. The paddles should not be sohot that they damage the fabric. Then, the paddles are removed and thepiece of fabric 17 which overlays the glue lines is peeled away takingwith it a portion of the melted glue. If desired, any remaining glue maybe scraped away with a hot knife. For some cellular products only asingle paddle may be sufficient to melt the glue. Upon completion ofthis process the cellular structure will have a small portion 4 a, 5 aofthe original glue lines on the cell 2. Those portions are shown in FIG.The method illustrated in FIG. 6 can be used only when the original glueis a low temperature thermoplastic adhesive. Such adhesives typicallyhave a melting temperature at 350° F. or less. After the cellularstructure has been prepared by grinding or melting as illustrated inFIGS. 2 and 6, a new glue line 20 is applied over the remaining glueportions 4 aand 5 a. The cellular structure is then ready to be bondedto another cellular segment.

Yet another method of removing the old glue is to use a laser to heatand soften the original glue so that it can be peeled or scraped away.

Another way of removing much of the original adhesive 4, 5 is to freezethe glue and then crack the glue away from the original cell 2. Yetanother method is to apply a solvent such as methylene chloride whichwill dissolve the glue allowing much of it to be removed. The selectedsolvent should not damage the fabric.

When the new glue line 20 is applied as shown in FIG. 8 that line may bewider than the original glue line. This will assure that when the twosegments are bonded together there will be an even bond along the frontof the shade. However, the new glue line should extend only a slightdistance beyond the original glue line, preferably not more than 1millimeter, so that the cells around the bond area of the two segmentsdo not appear to be differently shaped than other cells in the combinedstack.

After the segments have been prepared as described and a new glue linehas been provided as shown in FIGS. 7 and 8, the segments 1 and 21 arejoined together as illustrated in FIG. 9. For most adhesives the glueline is placed on only one segment. If a two part adhesive is used onepart is applied to one segment 1 and the second part is applied to thesecond segment 21. The resulting bond will be only 1 to 2 thousands ofan inch thick. Such a bond is not perceptibly thicker than any otherbond in the segments being joined. Consequently, a casual observer wouldnot know that the finished product was made from two or more segments ofcellular material.

We prefer that the new glue 20 which is used to bond segments togetherbe a high temperature adhesive which will not melt when holes aredrilled through the glue for lift cords. However, any adhesive commonlyused to make window coverings can be used.

A fixture or other equipment will be used to combine the two segmentstogether. Suitable equipment is described in U.S. Pat. No. 6,019,864 toJones which is incorporated herein by reference. Preferably, theequipment will have a wall or other structure against which the frontpleats of the stack abut. The glue applicator is a selected distancefrom that wall, such as 5 to 10 millimeters, and moves along a pathparallel to the wall. This assures that the glue line will be theselected distance from, and parallel to, the front pleats. In oneembodiment the glue applicator is positioned on the lower segment. Thenthe upper segment is placed on top of the lower segment and glueapplicator. The glue applicator moves between the two segments parallelto the front pleats applying glue as it moves. The weight of the uppersegment may be sufficient to press the two segments together and achievethe desired bond. In this embodiment the segments lie in a verticalplane. If desired, the segments could be on a flat or inclined tablewhen being joined together.

The method we have described for joining segments of cellular materialscan also be used for joining segments of tabbed material in which eachtab is comprised of two layers of fabric connected together by at leastone glue line. Such segments 30, 31 are shown in FIGS. 10 and 11. Whenthe process begins tabbed segment 30 has a top tab 34 having a bottomlayer of fabric 35, at least one glue line 36 on the bottom layer offabric and a top layer of fabric 37 on the at least one glue line. Usingany of the techniques described above for removing the strip of fabricfrom the top cell in the segment of cellular material, we first removethe top layer of fabric 37 and at least a portion of the glue line 36from the bottom layer 35 of the top tab 34. Next we apply at least oneglue line 38 to the bottom layer of fabric 35 of the top tab. That newglue line is shown in FIG. 11. Next we select a second segment of tabbedmaterial 31 in which the bottom tab 41 is a single layer of material.This single layer could have been created from tab comprised of twolayers of fabric glued together by removing the outermost layer offabric and a portion of the glue or may have been made to have only asingle fabric layer. Next we place tab 41 onto glue line 38 on thebottom layer 35 of the top tab 34 of segment 30 and allow the glue tocure thereby bonding the second segment of tabbed material 31 to thefirst segment of tabbed material 30.

Although we have illustrated single cell materials, our invention is notso limited. Our process could be used for double cell or othermulti-cell materials.

1. A method for making a window covering from segments of cellularmaterial containing a plurality of cells comprising: selecting a firstsegment of cellular material in which there is a top cell having a topsurface, at least one glue line on the top surface and a strip of fabricon the at least one glue line; removing the strip of fabric and at leasta portion of the at least one glue line from the top surface of the topcell; applying at least one second glue line to the top surface of thetop cell; selecting a second segment of cellular material; placing thesecond segment of cellular material over the at least one second glueline on the top surface of the top cell: allowing the at least onesecond glue line to cure thereby bonding the second segment of cellularmaterial to the first segment of cellular material.
 2. The method ofclaim 1 wherein the strip of fabric and at least a portion of the atleast one glue line are removed from the top surface of the top cell byat least one of milling, cutting, grinding and sanding.
 3. The method ofclaim 1 wherein the strip of fabric and at least a portion of the atleast one glue line are removed from the top surface of the top cell byheating the at least one glue line to soften the at least one glue lineand peeling away the strip of fabric and a portion of the at least oneglue line.
 4. The method of claim 3 also comprising scraping away asecond portion of the at least one glue line after peeling away thestrip of fabric and a portion of the at least one glue line.
 5. Themethod of claim 3 wherein the at least one glue line is comprised of athermoplastic adhesive and is heated by placing at least one heatedpaddle adjacent the top surface of the top cell.
 6. The method of claim3 wherein the at least one glue line is heated by a laser beam.
 7. Themethod of claim 1 wherein first segment of cellular material and thesecond segment of cellular material are a single cell cellular materialor double cell cellular material.
 8. The method of claim I wherein thestrip of fabric and at least a portion of the at least one glue line areremoved from the top surface of the top cell by freezing and thencracking the at least one glue line.
 9. The method of claim 1 whereinthe strip of fabric and at least a portion of the at least one glue lineare removed from the top surface of the top cell by applying a solventto the at least one glue line, allowing at least a portion of the atleast one glue line to dissolve and pulling the strip of fabric and atleast a portion of the at least one glue line away from the top surfaceof the top cell.
 10. The method of claim 9 wherein the solvent ismethylene chloride.
 11. A method for making a window covering fromsegments of cellular material containing a plurality of cellscomprising: selecting a first segment of cellular material in whichthere is a top cell having a top surface, at least one glue line on thetop surface and a strip of laminated fabric on the at least one glueline, the strip of laminated fabric having a plurality of layers;removing all but one of plurality of layers of the strip of laminatedfabric from the top surface of the top cell such that one layer of theplurality of layers remains on the top surface of the top cell; applyingat least one second glue line onto the one layer of the plurality oflayers that remains on the top surface of the top cell; selecting asecond segment of cellular material; placing the second segment ofcellular material over the at least one second glue line on the topcell; and allowing the at least one second glue line to cure therebybonding the second segment of cellular material to the first segment ofcellular material.
 12. The method of claim 11 wherein all but one ofplurality of layers of the strip of laminated fabric are removed fromthe top surface of the top cell by at least one of milling, cutting,grinding and sanding.
 13. The method of claim 11 wherein first segmentof cellular material and the second segment of cellular material are asingle cell cellular material or double cell cellular material.
 14. Amethod for making a window covering from a segment of cellular materialcontaining a plurality of cells comprising: selecting a segment ofcellular material having a known width; cutting the segment of cellularmaterial having a known width into at least two smaller segments ofcellular material, each smaller segment having a selected width smallerthan the known width, a first one of the smaller segments having a topcell having a top surface, at least one glue line on the top surface anda strip of fabric on the at least one glue line; removing the strip offabric and at least a portion of the at least one glue line from the topsurface of the top cell; applying at least one second glue line to thetop surface of the top cell; selecting a second one of the smallersegments of cellular material; placing the second one of the smallersegments of cellular material over the at least one second glue line onthe top surface of the top cell: allowing the at least one second glueline to cure thereby bonding the second one of the smaller segments ofcellular material to the first one of the smaller segments of cellularmaterial.
 15. The method of claim 14 wherein the strip of fabric and atleast a portion of the at least one glue line are removed from the topsurface of the top cell by at least one of milling, cutting, grindingand sanding.
 16. The method of claim 14 wherein the strip of fabric andat least a portion of the at least one glue line are removed from thetop surface of the top cell by heating the at least one glue line tosoften the at least one glue line and peeling away the strip of fabricand a portion of the at least one glue line.
 17. The method of claim 16also comprising scraping away a second portion of the at least one glueline after peeling away the strip of fabric and a portion of the atleast one glue line.
 18. The method of claim 16 wherein the at least oneglue line is comprised of a thermoplastic adhesive and is heated byplacing at least one heated paddle adjacent the top surface of the topcell.
 19. The method of claim 16 wherein the at least one glue line isheated by a laser beam.
 20. The method of claim 14 wherein first segmentof cellular material and the second segment of cellular material are asingle cell cellular material or double cell cellular material.
 21. Themethod of claim 14 wherein the strip of fabric and at least a portion ofthe at least one glue line are removed from the top surface of the topcell by freezing and then cracking the at least one glue line.
 22. Themethod of claim 14 wherein the strip of fabric and at least a portion ofthe at least one glue line are removed from the top surface of the topcell by applying a solvent to the at least one glue line, allowing atleast a portion of the at least one glue line to dissolve and pullingthe strip of fabric and at least a portion of the at least one glue lineaway from the top surface of the top cell.
 23. The method of claim 22wherein the solvent is methylene chloride.
 24. A method for making awindow covering from a segment of tabbed material having a plurality oftabs wherein each tab is comprised of two layers of fabric connectedtogether by at least one glue line comprising: selecting a segment oftabbed material having a known width; cutting the segment of tabbedmaterial having a known width into at least two smaller segments oftabbed material, each smaller segment having a selected width smallerthan the known width, a first one of the smaller segments removing thetop layer of fabric and at least a portion of the at least one glue linefrom the bottom layer of fabric of the top tab; applying at least onesecond glue line to the bottom layer of fabric of the top tab; selectinga second one of the smaller segments of tabbed material; placing thesecond one of the smaller segments of tabbed material over the at leastone second glue line on the bottom surface of the top tab; and allowingthe at least one second glue line to cure thereby bonding the second oneof the smaller segments of tabbed material to the first one of thesmaller segments of tabbed material.
 25. A method for making a windowcovering from segments of tabbed material having a plurality of tabswherein each tab is comprised of two layers of fabric connected togetherby at least one glue line comprising: selecting a first segment oftabbed material having a top tab, the top tab having a bottom layer offabric at least one glue line on the bottom layer of fabric and a toplayer of fabric on the at least one glue line; removing the top layer offabric and at least a portion of the at least one glue line from thebottom layer of fabric of the top tab; applying at least one second glueline to the bottom layer of fabric of the top tab; selecting a secondsegment of tabbed material; placing the second segment of tabbed overthe at least one second glue line on the bottom surface of the top tab;and allowing the at least one second glue line to cure thereby bondingthe second segment of tabbed material to the first segment of tabbedmaterial.